It is known that the intervertebral discs may be subject to compression, herniation, or arthritic intervertebral degeneration.
To manage the patients, there are techniques that require a surgical intervention.
A first technique involves replacement of the damaged disc with an intervertebral disc prosthesis. Such a replacement procedure is difficult for the surgeon to perform and poses a risk of loosening under the effect of the considerable shearing forces that arise in particular when the prosthesis is in the position of maximum flexion.
A second technique involves performing intervertebral arthrodesis, an operation by which the two vertebrae adjacent to the damaged disc can be fused. This blocks the degeneration of the disc, on account of the suppression of any mobility between the two vertebrae concerned.
Such a technique entails the use of a device for stabilizing the two vertebrae, device generally having screws which are intended to be screwed into the vertebrae and connected to each other by a rigid connection member. It is thus possible to avoid excessive mechanical stresses being applied to the intervertebral disc.
Here again, there are disadvantages in particular in requiring screwing into the vertebrae, which is a structurally aggressive operation that weakens the vertebrae concerned, or which is in fact impossible if the vertebrae are in a poor condition and/or are insufficiently wide at the attachment region.
Another technique involves the use of hooks. This approach, however, is a very delicate one, since the operating surgeon must not touch the spinal cord, in order to avoid paralyzing the patient. These are also risks of the hooks slipping and/or of the hooks coming loose.